Impact of Power Transformer Insulating Mineral Oil Degradation on FRA Polar Plot

Frequency response analysis (FRA) has been employed as an effective tool for the detection of various mechanical winding and core deformations within electrical power transformer. Traditional FRA signature interpretation relies on the magnitude of the FRA plot although all practical frequency response analyzers are able to provide both magnitude and angle of the FRA signal in wide frequency range. Moreover, no attention has been given to the impact of power transformer insulating oil degradation on the FRA signature. This paper presents is aimed at introducing a new interpretation approach of the FRA signature using polar plot which is obtained by incorporating FRA signature magnitude and phase into one plot. The paper also investigates the impact of insulating mineral oil degradation on the proposed polar plot signature. Digital image processing (DIP) technique is developed to automate the interpretation process. In this regard, the physical geometrical dimension of a single-phase transformer filled with insulating mineral oil is simulated using three-dimensional finite element analysis to emulate real transformer operation. FRA polar plot signatures are measured and analyzed for various health conditions of the mineral oil. Results show that insulating mineral oil degradation has an impact on the transformer FRA polar plot signature. The proposed FRA polar plot technique is easy to implement within any frequency response analyzer

Contemporary Trends in the Use and Outcomes of Surgical Treatment of Tricuspid Regurgitation

Background Tricuspid regurgitation (TR), if untreated, is associated with an adverse impact on long‐term outcomes. In recent years, there has been an increasing enthusiasm about surgical and transcatheter treatment of patients with severe TR. We aim to evaluate the contemporary trends in the use and outcomes of tricuspid valve (TV) surgery for TR using the National Inpatient Sample. Methods and Results Between January 1, 2003 and December 31, 2014, an estimated 45 477 patients underwent TVsurgery for TR in the United States, of whom 15% had isolated TV surgery and 85% had TVsurgery concomitant with other cardiac surgery. There was a temporal upward trend to treat sicker patients during the study period. Patients who underwent isolated TV repair or replacement had a distinctly different clinical risk profile than those patients who underwent TVsurgery simultaneous with other surgery. Isolated TV replacement was associated with high in‐hospital mortality (10.9%) and high rates of permanent pacemaker implantation (34.1%) and acute kidney injury requiring dialysis (5.5%). Similarly, isolated TV repair was also associated with high in‐hospital mortality (8.1%) and significant rates of permanent pacemaker implantation (10.9%) and new dialysis (4.4%). Isolated TV repair and TV replacement were both associated with protracted hospitalizations and substantial cost. Conclusions In contemporary practice, surgical treatment of TR remains underused and is associated with high operative morbidity and mortality, prolonged hospitalizations, and considerable cost

A valid treatment option for isolated congenital microgastria

Congenital microgastria (CM) is an extremely rare anomaly of the caudal part of the foregut. Treatment of CM has not yet been standardized. We present the case of a 34-monthold girl with an isolated CM complicated by nasogastric tube-related gastric perforation. During the definitive reconstructive surgery, a scarred structure (1.5 1.5 cm) was found to follow a dilated esophagus. The scarred microstomach was resected, and a Roux-en-Y esophagojejunostomy was performed. The patient has been followed for 6 months. She tolerates a regular oral diet and has reached acceptable growth parameters. We describe the first case of CM to be treated with resection of the microstomach and with a Roux-en-Y esophagojejunostomy.Keywords: congenital microgastria, gastrectomy, Roux-en-Y esophagojejunostom

What’s Happening Around the World? A Survey and Framework on Event Detection Techniques on Twitter

© 2019, Springer Nature B.V. In the last few years, Twitter has become a popular platform for sharing opinions, experiences, news, and views in real-time. Twitter presents an interesting opportunity for detecting events happening around the world. The content (tweets) published on Twitter are short and pose diverse challenges for detecting and interpreting event-related information. This article provides insights into ongoing research and helps in understanding recent research trends and techniques used for event detection using Twitter data. We classify techniques and methodologies according to event types, orientation of content, event detection tasks, their evaluation, and common practices. We highlight the limitations of existing techniques and accordingly propose solutions to address the shortcomings. We propose a framework called EDoT based on the research trends, common practices, and techniques used for detecting events on Twitter. EDoT can serve as a guideline for developing event detection methods, especially for researchers who are new in this area. We also describe and compare data collection techniques, the effectiveness and shortcomings of various Twitter and non-Twitter-based features, and discuss various evaluation measures and benchmarking methodologies. Finally, we discuss the trends, limitations, and future directions for detecting events on Twitter

Association between HindIII (rs320) variant in the lipoprotein lipase gene and the presence of coronary artery disease and stroke among the Saudi population

Lipoprotein Lipase (LPL) is known to be a key enzyme for lipid metabolism specifically in an enzymatic glycoprotein which provide tissues without fatty-acids and eliminates triglycerides (TG) by the circulation. Mutations in LPL were proven to cause alteration in fractions within lipoprotein, causing the development of atherosclerosis which predispose to weakening coronary artery disease (CAD) and stroke. We examined the linkage between genetic variant HindIII in LPL on lipoprotein fractions, stroke occurrences and CAD. In this case-control study, we have recruited 315 CAD cases and 205 age-matched controls. A total of 520 genomic DNA was digested with the purified PCR products for restriction fragment length polymorphism with HindIII restriction enzyme. The distribution of genotypes in a decreasing order were TT, 148 (47%), GT 135 (42.9%) and GG 32 (10.2%) in CAD groups of the study while the pattern in controls were GT 91 (44.4%), TT 86 (42%) and GG 28 (13.7%). None of all the allele or genotype frequencies were found to be significant in our study (p greater than 0.05), while the biochemical levels for both TG and LDL-c were shown to be prone in CAD patients when compare with the controls. Furthermore, the occurence of strokes were more in CAD groups vs. controls: 72 (22.9%) vs. 7 (3.4%) [p 0.000]. This could indicate the influence of HindIII variant on plasma lipid levels, and the possibility of considering it a risk factor for atherosclerosis leading to CAD and stroke occurrence

Imaging immunoassay in negative: Surface-­‐catalysed chemiluminescence for the detection of pregnancy hormones in artificial saliva

A novel and rapid (45min), quantitative chemiluminescence-based, surface immunoassay is reported for the quantitative detection of progesterone and œstriol in artificial saliva. The detection limits for these pregnancy hormones are 2.3 and 2.5 pg mL-1, respectively. The assay is based on the use of ferrocene- tagged, monoclonal antibodies immobilised on a surface, so that the oxidised ferricenium catalyses the reaction between luminol and hydrogen peroxide. The immunoassay is performed in negative, such that increasing the antigen concentration gives rise to decreasing light intensity that is observed, and is unaffected by antibody orientation on the surface. This affords a method of calibration that is readily translated to pregnancy hormone detection in a primary point-of-care environment. Biomolecules with similar structures to these pregnancy hormones found in saliva are demonstrated not to interfere with the immunoassay

Aspergillus fumigatus and aspergillosis: From basics to clinics

The airborne fungus Aspergillus fumigatus poses a serious health threat to humans by causing numerous invasive infections and a notable mortality in humans, especially in immunocompromised patients. Mould-active azoles are the frontline therapeutics employed to treat aspergillosis. The global emergence of azole-resistant A. fumigatus isolates in clinic and environment, however, notoriously limits the therapeutic options of mould-active antifungals and potentially can be attributed to a mortality rate reaching up to 100 %. Although specific mutations in CYP51A are the main cause of azole resistance, there is a new wave of azole-resistant isolates with wild-type CYP51A genotype challenging the efficacy of the current diagnostic tools. Therefore, applications of whole-genome sequencing are increasingly gaining popularity to overcome such challenges. Prominent echinocandin tolerance, as well as liver and kidney toxicity posed by amphotericin B, necessitate a continuous quest for novel antifungal drugs to combat emerging azole-resistant A. fumigatus isolates. Animal models and the tools used for genetic engineering require further refinement to facilitate a better understanding about the resistance mechanisms, virulence, and immune reactions orchestrated against A. fumigatus. This review paper comprehensively discusses the current clinical challenges caused by A. fumigatus and provides insights on how to address them.AA, RGR, and DSP were supported by NIH AI 109025. MH was supported by NIH UL1TR001442. AC was supported by the Fundação para a Ciência e a Tecnologia (FCT) (CEECIND/03628/2017 and PTDC/MED GEN/28778/2017). Additional support was provided by FCT (UIDB/50026/2020 and UIDP/50026/2020), the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF) (NORTE-01-0145-FEDER-000013 and NORTE-01-0145-FEDER-000023), the European Union's Horizon 2020 Research and Innovation programme under grant agreement no. 847507, and the “la Caixa” Foundation (ID 100010434) and FCT under the agreement LCF/PR/HP17/52190003. DJA was supported by CF Trust Strategic Research Centre TrIFIC (SRC015), Wellcome Trust Collaborative Award 219551/Z/19/Z and the NIHR Centre for Antimicrobial Optimisation.S